Crank connection for radial motors



Aug. 16, 1932.

J. NEWMANN 1,871,729

CRANK CONNECTION FOR RADIAL MOTORS Original Fiafid Sept 27. 1929 #1mmmnnw j M INVENTOR 0% efiomwe ATTORNEY Patented Aug. 16, 1932 PATENTFFlCE JOHN NEWMANN, or BROOKLYN, NEW YORK CRANK connncrron son RADIALMorons Refile of application Serial No. 395,508, filed' September 27,1929. This application filed July 17, 1931.

Serial No. 551,429.

The present case is a refiling of my application Serial No. 395,508,filed September,

27th, 1929. I

r The present invention relates to crank connections and while it isespecially adapted for radial motors for use on aeroplanes,the-invention is not necessarily limited to the em bodiment hereinshown, norto the specific use set forth. The invention relates to thattype of crank connection for radial motors wherein an annular bearingmember is integral with or connected to amaster connecting rod andwherein a plurality of connecting rods are pivotally connected with theannular bearing member so that a number of cylinders may be arrangedaround a common axis and have the connecting rods operating on a commoncrank. IVhile the invention is adapted for various uses wherever a crankthrow is provided on a shaft, it is especially adapted for the type ofradial motor above described. One of the objects of the invention is tol provide a crank connection wherein the num- '25 ber of parts 1sreduced to a minimum for the purpose of simplicity and economy and toreduce the total weight. Another object of the invention is to eliminatethe use of screws,

M, bolts and other threaded members in the crank connection, in order toeliminate the danger of threaded members becoming loosened by reason ofvibration or from the ordinary operation of the movable parts.

,. Another object is to permit the crank throw to be made of detachableparts, which may be assembled quickly and which will be rigid anddependable when in operative or assembled condition. Another object isto provide a construction permitting counterweightsto' throw has beenmade in one piece, in order to permit the bearing member to be assembledon the wrist pin of the crank throw. In other cases the crank throw hasbeen adapted to be disassembled in order to; permit a one piece bearingto be assembled on the wrist pin and permit parts of the crank throw tobe asobjects will be apparent from the following detailed description ofmy invention.

In the drawing forming part of this application,

Figure 1 is an elevation of a crank connection illustrating my'inventionin the preferred form and adapted for use with a radial motor and inthis view only one ofthe articulated connecting rods is illustratedforthe purpose of simplicity,

Figure 2 is an end elevation of the device in which view only one of thearticulated connecting rods .is shown the same as in Figure 1, p v

Figure .3 is a sectional View taken on the line 33 of Figure 2,

Figure 4: is an elevation partly in section, showing the parts of thecrank throw,

Figure 5 is a sectional view taken on the line 5-5 of Figure 4, and 1Figure 6 is a perspective view of a locking rey.

In the drawing I have shown two shaft sections 1 and 2 which aredisposed in axial alignment when the -members ofthe crank throw are inassembled condition, and this may represent the crank shaft of anaeroplane engine or any other type "of mechanism. On one of these shaftsections, to wit, the section 1. there is integrally'formed a laterallyprojecting arm 3 forming part of the crank throw and if desired thecounterweight l may be formed to extend in the opposite direction fromthe'shaft section 1 to the arm 3 for counterbalancing the opposedportions of the crank throw. The wrist pin 5 which projects at rightangles to the arm ed with it.

bore 12.

weight thereof andon its outer or free end the wrist pin is providedwith a notch or cut out 7 having an areuate surface 8 for the purposewhich will be pointed out hereinafter. f I r w The shaft section 2 hasformed integral therewith a crank arm'9 which also forms a part of thecrank throw and this arm is disposed at right angles to the axis of theshaft and parallel with the crank arm 3.

If desired the counterweight 10 may be formed integral with the shaftsection 2- to lie parallel with'the counterweight 4: so that bothcounterweights co-operateto counter: balance the crank throw and partsconnect- The crank arm 9 is provided with a lateral bore 11 to receivethe free end of the wrist-pin and this here is so proportioned as toform a pressing fit on the end of the wrist pin. Preferably it is soproportioned that a slight expansion is requiredin forcing the crank-armonto the end of the wrist pin. a g

It will be noted that the shaft section 2 is made hollow by providing alongitudinal I I have provided a slot or cut 13 which extends from thebore 11 which receives the wrist pin to the bore 12 of the shaftsections, the out being made in the metal forming the crank arm 9.. Thispermits the two sections 14;, 15 or halves of the crank arm 9 to beexpanded slightly in order to slightly enlarge the bore 11 when thecrank arm is being pressed or forced onto the end of the wrist pin sothat when the crank arm is in the assembled position shown in Figure 1the resiliency of the metal of which the crank arm is made will cause itto return to normal position and in so doing cause the end of the wristpin. to be grasped snugly in the bore 11.. p

In order to permit the section- 15 of. the crank arm to spring slightlythe manner described I form another cut 16 disposed in a plane at rightangles to the cut 13. i This latter cut 16 extends into the shaftsection 2 adjacent the cheek of the crank arm 9. This cut extends onlypartially through the shaft section as more clearly illustrated inFigure 5, so that the latteris unattached to the crank arm across thegap of the slot 13 and some distance below the same on one side. Thiscut 16 as stated herein is to permit the portions 14:, 15v on eachsideof the cut 18' toexpandslightly during the operation of applying thecrank: arm to the wrist in. p It its-necessary, assembling the crankthrow. to have the crank arms 3 and 9 in alignment and it is desirableto; provide means for indicating this alignment and for keeping themembers of the crank throw in alignment. For this purpose I haveprovided the key shown in Figure 6, which consists of a small plate 17having a curved bottom edge 18 corresponding with the curvature-of theshoulder 19 of the shaft section 2 and having a curved upper edge 20correformed an annular bearing member 23 having spaced parallel platesor flanges 24,. 25 between which is ahub 26 centrally located andprovided with a bore adapted to it onto the wrist pin 5. There arevarious articulatedconnccting rods 27 having heads. 28 disposed in thespace between the parallel flanges 24, 25' and these are connected withthe bearing member by means of knuckle pins 29. a

In assembling the device the bearingmem her 23 together with the masterconnecting rod 22 is inserted; over the free end of the wrist pin beforethe shaft section 2 and crank arm 9 are assembled. After the bearingmember 23 has been placed overthe wrist pin the shaft section 2 andcrank arm 9 may be assembled on the wrist pin. Preparatory to this thekey 17 is placed with its arcuate edge 18 resting on the flange 19 andwith the lug 21 projecting into the cut 13 The shaft section 2 and thecrank arm 9 7 arethen presented for assembly in position holds the key17 in the positionabove described and the crank arm 9 is pressed orforced onto" the free end of the wrist pin. In order to move the crankarm 9 into the fully assembled position the operator will be guided bythe key 17 so that he will cause the upper, arcuateedge 20 of the key toregister with. the curved shoulder 8 on the end of the wrist pin.

Ifthese parts are not inproper register it may beinecessary to slightlyturn the crank arm and shaft section in relation to the wrist pin inorderto make thetop edge 20 of the key register with the curved shoulder8 until the crank arm 9 is fully driven or pressed onto the wrist pin tothe position indicated in Figures 1, 2 and l. When the crank arm 9 isbeing pressed onto the end of the wrist pin the metal on opposite sidesof: the cut 13 can. expand slightly and its tendency to lit) return dueto the resiliency of the metal will cause the end of the wrist pin to betightly grasped within the bore 11. hen the upper edge 20 of the keyenters the notch 7 with i the curved edge 18 registering with theshoulder 19 the operator will be assured that the crank arms andcounterweights of the crank throw are in perfect alignment, due to theregistering action of the key.

Furthermore, while the device is in operation, the parts of the crankthrow will not get out of alignment and disturb the timing action of themotor, because of the presence of the key. The key is not required towithstand any great stresses because there is no great force tending tocause disalignment of the crank arms of the device.

When the parts are fully assembled the casing 30 of the roller or ballbearing in which the shaft section 2 is mounted will lie against theface or adjacent the face of the key 17, as shown in Figure 1, and thusprevent the key from being dislodged. The key is held from movingupwardly or downwardly by engagement with the flange l9 and with thewrist pin and it is held in one direction] by the check of the crank arm9 so that when the cage 30 of the bearing of the shaft section is inposition the key is held against displacement in all directions. Thiskey forms a simple means for securing accurate alignment of the crankarms during the assembling operation and it avoids the necessity ofproviding threaded parts on the crank throw for securing and maintainingalignment.

It will be apparent from the above that I have provided a simple butsubstantial crank throw for radial motors of a two-piece type whichpermits of partial disassembly for the purpose of mounting a one-piecemaster rod and bearing on the wrist pin and which permits the two piececrank throw to be quickly assembled after the bearing member has beenpositioned. The construction insures a tight fit between the detachablecrank arm and the wrist pin without the use of threaded members.

Having described my invention, what I claim'is:

1. In a crank construction for motors, the combination of a shaftcomposed of aligned sections, a crank arm on one of said sections, awrist pin on said crank arm, a second crank arm on the second shaftsection, said latter crank arm having an aperture to receive said wristpin, said second shaft section having a central bore, said second crankarm and second shaft section having a cut or slot extending from thewrist pin aperture of said second crank arm to the bore of said second,

crank section and said second shaft section having a cut extendinginwardly thereof adjacent said second crank arm and crossing the planeof said first cut.

2. In a crank construction for motors, the combination of a shaftsection, a crank arm thereon, a wrist pin on said crank arm having anotch adjacent the free end thereof, a second shaft section, acrankarmthereon provided with a bore to receive said wrist pin, saidsecond crank arm having a cut'or slot extending from said wrist pin boreto'permit said second crank arm to be sprung over said Wrist pin, and amember having a portion engaging in said out and having a portionextending into the notch of said Wrist pin.

3. In a crank construction for motors, the combination of a shaftsection, a crank arm thereon, a wrist pin on said crank arm having anotch on the free end thereof, a second shaftsection, a second crank armthereon, provided with a bore to receive said wristpin, said secondcrank arm having a cut extending from said bore, a key having a curvedsurface for engaging a portion of said second shaft section, and havinga portion projecting into the notch of said wrist pin, and having atonguev extending into said out, said key securing the alignment of saidcrank arms.

4. In a crank construction for motors, the combination of a shaftsection, a crank arm thereon, a Wristpin on said crank arm, said wristpin having a notch in the free end thereof, a second shaft section, acrank arm thereon, provided with a bore to receive the end of the wristpin, a key adapted to slide lengthwise of said wrist pin and to engagein the notch of said wrist pin and lie against the cheek of said secondcrank arm, said key having means engaging said second crank arm tosecure alignment of said crank arms.

Signed at the city, county and State of New York, the 24th day of June,1931.

JOHN NEWMANN.

CERTIFICATE OF CORRECTION.

Patent No. 1,871,729. August 16, 1932.

JOHN NEWMANN.

It is hereby certified that the above numbered patent was erroneouslyissued to the inventor said "Newmann" whereas said patent should havebeen issued to Charles G. Hensley, of New York, N. Y., Receiver of saidJohn Newmann, as shown by the records of assignments in this office; andthat the said Letters Patent should be read with this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 22nd day of November, A. D. 1932.

M. J. Moore,

Acting Commissioner of Patents.

(Seal)

